This invention relates generally to refueling systems and related fuel nozzles for use in rapid yet safe refueling of a race car during an automobile race. More specifically, this invention relates to an improved fuel nozzle and related refueling system components for achieving faster and safer refueling of a race car during a pit stop.
Modern automobile racing is an extremely popular spectator sport which attracts the attention of millions of fans throughout the world. Modern race cars are the culmination of sophisticated and costly engineering technologies, including structural frames and materials, aerodynamic designs, and specialized engines. Professional race teams literally spend millions of dollars to develop and maintain a modern race car, such as a so-called Indianapolis type car, for competition in several racing events over the course of a single racing season. Competition among these professional race teams for sponsorship money is intense and the pressure to succeed on the race track is great.
In recent years, the development of race car technology has proceeded in parallel with efforts to improve car and driver safety. To this end, the design and capacity of fuel tanks or fuel cells on the race car have evolved in efforts to reduce the likelihood of explosion and/or fire in the event of a mishap on the race course. Similarly, considerable attention has been given to the prevention of fuel spillage in the pits when a race car is refueled during a race. Prevention of explosion and/or fire in the pits is of special concern in view of the presence of multiperson pit crews as well as the frequent close proximity of spectators. The hazards presented by a fuel-fed fire are particularly critical when a fuel is used such as methanol which burns with a colorless or invisible flame.
By way of further example, over the past few decades, the on-board fuel capacity of a typical race car has been progressively reduced so that the cars carry less fuel during a race, thereby reducing the chances of a fuel spillage and/or fire should a mishap occur. This reduction in fuel tank capacity, however, has necessitated a greater number of pit stops during a typical race event. In this regard, although tire changes and other service activities may be performed during a routine pit stop, the duration of most pit stops is related primarily to the time needed to refill the fuel cell on the car so that the car can resume the race. For any car to be competitive, it is essential for the cumulative time in the pits to be as short as possible. In a typical long distance race, such as the Indianapolis 500, each race car can require 7-10 or more pit stops in order to complete the race. As the race progresses, the speed and efficiency of each pit stop also increases to in effect create a secondary race among pit crews that can be equally important to the primary race on the track. With this in mind, improvements in refueling safety are needed.
Refueling systems for race cars are the subject of specific rules and regulations aimed at preventing safety compromises in order to achieve faster car refueling times. For example, in race events for Indianapolis type cars sponsored by the United States Auto Club (USAC) or Championship Auto Racing Teams (CART), each team is provided with an elevated pitside fuel tank containing a prescribed quantity of approved fuel for use by a single car during a race event. The fuel flows by gravity through a fuel hose to a fuel nozzle adapted for quick-connect coupling with a mating receiver on the car. Such nozzle-receiver connection opens a fuel flow valve in the nozzle, typically in the form of a pivoting butterfly valve plate, to permit gravity drainage of fuel from the pitside tank to the car fuel cell. At the same time, a vent port at the top of the car fuel cell is opened to allow air escape from the fuel cell and thereby permit fuel entry via the fuel nozzle. The vent port is coupled through an overflow vent valve and a recovery hose for recapturing and recycling fumes and overflow fuel to the pitside fuel tank, so that no fuel is spilled or lost. The vent valve typically includes a sight glass to permit viewing of fuel flow therein when the fuel cell reaches a filled condition, at which time the vent port is closed and the fuel nozzle is disengaged from the car. Disengagement of the nozzle from the car is accompanied by closure of the fuel flow valve.
The present invention relates to a race car refueling system of the gravity drain type, as generally described above, but wherein an improved fuel nozzle permits fuel flow to the car at a comparatively faster flow rate but with greater safety, whereby the race car can be refueled in a shorter period of time. By reducing the refueling time needed for each pit stop, the refueling system of the present invention permits a race car to be more competitive particularly during long distance races, by significantly reducing the cumulative time spent in the pits.